#include<cstdio>

int main()
{
	int i, k;
	double sum;
	scanf("%d",&k);
	i = 0;
	sum = 0;
	while(sum <= k)
	{
		i = i + 1;
		sum = sum + (double)1/i;
	}
	printf("%d",i);
	return 0;
}
